I agree with the other monks that you probably should use a better data structure. However, you can use the Schwartzian Transform described in the FAQ to solve the original problem. 
$type 1227601.pl
use strict;
use warnings;
use Data::Dumper;

my $ArrayofHash = [
    {   'TaskA' => {
            'maruti'  => '20',
            'honda'   => '25',
            'zen'     => '25',
            'hyundai' => '35',
            'ford'    => '22',
            'toyota'  => '11'
        }
    },
    {   'TaskB' => {
            'maruti'  => '11',
            'honda'   => '22',
            'zen'     => '33',
            'hyundai' => '33',
            'ford'    => '24',
            'toyota'  => '16'
        }
    },
    {   'TaskC' => {
            'maruti'  => '12',
            'honda'   => '22',
            'zen'     => '33',
            'hyundai' => '44',
            'ford'    => '55',
            'toyota'  => '66'
        }
    }
];

my $sorted = [
    map {$_->[1]}
        sort {$b->[0] <=> $a->[0]}
            #map {(my $h) = values %$_; [$h->{hyundai}, $_]}
            map {[(values %$_)[0]{hyundai}, $_]}
                 @$ArrayofHash
];

print Dumper($sorted);

$perl 1227601.pl
$VAR1 = [
          {
            'TaskC' => {
                         'zen' => '33',
                         'toyota' => '66',
                         'maruti' => '12',
                         'hyundai' => '44',
                         'honda' => '22',
                         'ford' => '55'
                       }
          },
          {
            'TaskA' => {
                         'ford' => '22',
                         'toyota' => '11',
                         'maruti' => '20',
                         'hyundai' => '35',
                         'honda' => '25',
                         'zen' => '25'
                       }
          },
          {
            'TaskB' => {
                         'ford' => '24',
                         'honda' => '22',
                         'hyundai' => '33',
                         'maruti' => '11',
                         'toyota' => '16',
                         'zen' => '33'
                       }
          }
        ];

$

[download]

UPDATE: Modified code to simplify dereference. Note: Using the first (and only) element of values avoids the problem with not knowing the name of the key.

Bill

In reply to Re: need to sort array of hash by BillKSmith
in thread need to sort array of hash by Anonymous Monk

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